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diff --git a/docs/tutorials/014/page01.html b/docs/tutorials/014/page01.html deleted file mode 100644 index 1be24af0723..00000000000 --- a/docs/tutorials/014/page01.html +++ /dev/null @@ -1,72 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="Bob McWhirter"> - <TITLE>ACE Tutorial 014</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 014</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>ACE_Stream Tutorial, Of Sorts</FONT></B></CENTER> - -<P> -<HR WIDTH="100%"> - -<p><b>ACE_Stream</b> is handy when you have several <b>ACE_Task</b> objects -that you would like to link together. - -<p>An intermediate class you we will deal with is the <b>ACE_Module</b>. - -<p>The basic plan is to wrap your <b>Task</b> into a <b>Module</b>, push -the <b>Module</b> onto the <b>Stream</b>. Do this for each <b>Task</b>, - and then inject <b>Message_Block</b>s into the <b>Stream</b>. - -<p>Each <b>Task</b> then processes the <b>Message_Block</b>, and forwards -it on to the next <b>Task</b> in the <b>Stream</b>. - -<p>If you are not already familiar with <b>Message_Block</b>s and <b>Message_Queue</b>s, -I highly suggest that you check out <A HREF="../#MQ">Tutorials 10-13</A>. - -<p>Streams can be used for both downstream and upstream movement of messages. Used -this way mirrors closely the way System V STREAMS work. But you don't have to use them -bidirectionally. In this tutorial, we only use one direction of the Stream. Down. - -<p>This tutorial is contributed by Bob McWhirter (bob@netwrench.com) - -<P> -Kirthika's abstract: -<ul> -In this tutorial, an ACE_Stream has been implemented which has modules -flowing through it.(literally ;). -The chain of modules in the Stream include the Head and Tail Modules. A -Module is simply a reader-writer pair of ACE_Tasks with the writing side -acting as downstream and the reading side as upstream. Here we are only -concerned with going downstream so we install a Task into the write-side -of the module. -<P> -The task implementation makes use of flags to decide on whether to close -the main task or the service thread. The svc () method follows the -golden rule of copying message blocks before putting them on the queue -until it comes across a hang-up message. It then puts the message back -on the queue for its peers to obtain it and exits. -<P> -Any message put onto the Tail module is an error. So a customised -derivative of the Task class is created, which collects all the garbage -messages put onto the Tail. This End_Task is put into the Stream at the -start itself such that no modules whould ever follow it! -<P> -Then the other modules are pushed from the Tail-end into the Stream. -This is because we are interested in writing and not reading. -(Picture this to be a FIFO (queue) with head and tail nodes such -that the nodes are removed from the front and put into the queue from -the back) -<P> -Each module then opens up the task which spawns threads and begins to -shove messgaes down the stream. Once we have got all the messages into -the stream, our job is completed and we shut down the Stream. -<P> -A simple way to wade down the stream...;) -</ul> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page02.html">Continue This Tutorial</A>]</CENTER> |